1. Field of the Invention
A certain aspect of this disclosure relates to an antenna including a slot and a windshield including the antenna.
2. Description of the Related Art
There exists a known windshield including a conductive layer in which a slot is formed so that the conductive layer functions as an antenna (see, for example, WO 2011/004877). The antenna disclosed in WO 2011/004877 includes a pair of electrodes that face the conductive layer across a glass plate. The antenna is configured such that the slot formed in the conductive layer is disposed between the electrodes when the electrodes are projected onto the conductive layer, and the electrodes and the conductive layer are capacitively coupled. The configuration of WO 2011/004877 where a conductive layer is formed on a windshield makes it possible to receive a desired radio wave even when there is no space for installing a linear conductor antenna of the related art.
However, a high antenna gain is required for an antenna provided on a windshield so that the antenna can function in various environments. Even in the case of an antenna using a conductive film as disclosed in WO 2011/004877, it is desired to further improve the antenna gain.